1. Modular Hadamard matrices and related designs;Butson;J. Combinatorial Theory, Ser. A,1973
2. Modular Hadamard matrices and related designs, II;Butson;Canad. J. Math.,1972
3. Sui determinauti di valore massimo;Scarpis;Rend. R. Inst. Lombardo Sci. Lett.,1898
4. Combinatorics: Room Square Designs, Sum-Free Sets, Hadamard Matrices;Wallis,1972
5. Hadamard's determinant theorem and the sum of four squares;Williamson;Duke Math. J.,1944